A Binary Asteroid

This time-lapse video was put together from Hubble Space Telescope photos. It shows two asteroids with comet-like features orbiting each other. The asteroid pair, called 2006 VW139/288P, was observed in 2016, just before its closest approach to the Sun. The photos reveal the binary system has a tail like a comet. The apparent movement of the tail is caused by changes in the relative alignment between the Sun, Earth, and 2006 VW139/288P between observations. The tail orientation is also affected by a change in the particle size. The pair was emitting relatively large particles (about 1 mm) in late July, and the tail was pointing in more or less the same direction as most of the particle emissions. However, after 20 September, 2016, the tail began to point in the opposite direction as pressure of sunlight pushed smaller (about 10 µm) dust particles away from the Sun.

Credits: NASA, ESA, and J. DePasquale and Z. Levay (STScI)

A New Moon

A moon was discovered around the dwarf planet 2007 OR10 in these archival Hubble images. They were taken a year apart and reveal a moon orbiting the dwarf planet. Each image, taken by the Hubble Space Telescope‘s Wide Field Camera 3, shows the companion in a different position around the planet. 2007 OR10 is the third-largest known dwarf planet, after Pluto and Eris, and the largest unnamed body in the solar system. It’s located in the Kuiper Belt, a realm of icy debris left over from the solar system’s formation.

Image Credits: NASA / ESA / C. Kiss (Konkoly Observatory) / J. Stansberry (STScI)

The Rings of Uranus

Saturn’s rings are so prominent that they easily visible from Earth with a small telescope. All the other gas giant planets have ring as well, but they weren’t discovered until we were able to look at those planets from above the Earth’s atmosphere. Here are some pictures of the ring system around Uranus taken by the Hubble Space Telescope as our point of view shifted over several years. The next time the rings will be edge-on will be in 2049.

Image Credit: NASA / ESA / STScI

The Case of the Runaway Quasar

This Hubble image is an unusual sight—a runaway quasar fleeing from its galaxy’s central hub. A quasar is the visible, energetic signature of a black hole, The black hole cannot be seen directly, but it’s the energy source at the heart of its quasars. The quasar, in turn, is an intense, compact source of radiation that can outshine an entire galaxy.

The green dotted line marks the visible boundary of the galaxy. The quasar, called 3C 186, appears as if it were a bright star just off-center, and it’s moving rapidly away from the galactic center. The force involved is roughly equivalent to the energy of 100 million supernovas exploding simultaneously. One plausible explanation for this propulsive energy is that the quasar is being pushed by gravitational waves unleashed by the merger of two other black holes at the center of the galaxy.

Image Credit: NASA / ESA / STScI

The Orion Nebula in False Color

This false color image of the Orion Nebula was generated using visible light and infrared data from two of the instruments onboard the Hubble Space Telescope. The image shows a segment of the sky about 0.002° wide. That works out to around 3.4 light-years at the nebula which is 1,500 light-years away.

Image Credit: Nasa / ESA / STScI

The Fireworks Galaxy

NGC 6946 is known as the Fireworks Galaxy, In the past century, nine supernovae have been observed to explode in its spiral arms. This makes it the most prolific known galaxy for this type of event over a period of 100 years. By comparison, the Milky Way galaxy, which has twice as many stars as NGC 6946, averages one supernova event per century.

Image Credits: NASA, ESA, STScI, R. Gendler, and the Subaru Telescope (NAOJ)